Speciation is the
process by which new and distinct species are formed. One of the most important
factors necessary for speciation to occur is the genetic isolation of two
populations. This genetic isolation can, over long periods of time, cause these
two groups to become genetically incompatible. Factors that can lead to this
genetic isolation include geographic separation and hostility among population
groups.
Answer:
Fossil B is the same age as the index fossil.
Explanation:
TOO LATE BUSTER
<span>The respiratory system deals with the body's breathing system, including the mouth, throat and lungs. An example of something the respiratory system doesn't do is anything with the digestive system. The digestive system consists of the mouth, throat, stomach, intestines and colon. It processes food and liquids into nutrients and energy for the body.</span>
Answer:
The embryo without starch OR cotyledon
Explanation:
Starch agar can be described or explained as a differential medium that tests the ability of an organism to produce certain exoenzymes, including a-amylase and oligo-1,6-glucosidase, that hydrolyze starch.
It should be understood that, the inclusion or addition of starch makes it a rich medium for those bacteria possessing the enzyme alpha-amylase, which breaks starch down to its component glucose molecules.
Therefore, in this case, any plant embryo that does not contain starch will be unable to grow.
Glucose is the preferable source of energy for E. coli cells. By adding small amounts of glucose, 0.05% in this case, it would enable cell growth to proceed as usual until it has reached mid log growth phase. At this point, the small amount of glucose added should have been depleted and the E.coli cell will now be dependent on lactose present as its source of nutrients. Lactose will also inactivate lac repressors and given the lack of glucose, CAP binding to high amounts of cAMP will be activated and increase expression of lac operon genes.
It should be noted that this system of expression may not tightly regulate the expression of lac operon before the E.Coli reaches exponential phase. As lactose is still present, lac repressors will be inactivated throughout the entire experiment and hence small amounts of proteins might be produced even when not auto-induced. After auto-induction, CAP-cAMP protein complex will simply upregulate expression of lac operon genes.
